Sterile abscesses in glioma patients treated by intraparenchymal injection of lymphokine-activated killer cells and recombinant interleukin-2: case reports

Treatment outcomes for ARUBA-eligible brain arteriovenous malformations: a comparison of real-world data from the NVQI-QOD AVM registry with the ARUBA trial

BACKGROUND

Significant controversy exists about the management of unruptured cerebral arteriovenous malformations (AVMs). Results from A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA) suggested that intervention increases the risk of stroke/death compared with medical management. However, numerous study limitations raised concerns about the trial's generalizability.

OBJECTIVE

To assess the rate of stroke/death and functional outcomes in ARUBA-eligible patients from a multicenter database, the Neurovascular Quality Initiative-Quality Outcomes Database (NVQI-QOD).

METHODS

We performed a retrospective analysis of prospectively collected data of ARUBA-eligible patients who underwent intervention at 18 participating centers. The primary endpoint was stroke/death from any cause. Secondary endpoints included neurologic, systemic, radiographic, and functional outcomes.

RESULTS

173 ARUBA-eligible patients underwent intervention with median follow-up of 269 (25-722.5) days. Seventy-five patients received microsurgery±embolization, 37 received radiosurgery, and 61 received embolization. Baseline demographics, risk factors, and general AVM characteristics were similar between groups. A total of 15 (8.7%) patients experienced stroke/death with no significant difference in primary outcome between treatment modalities. Microsurgery±embolization was more likely to achieve AVM obliteration (P<0.001). Kaplan-Meier survival curves demonstrated no difference in overall death/stroke outcomes between the different treatment modalities' 5-year period (P=0.087). Additionally, when compared with the ARUBA interventional arm, our patients were significantly less likely to experience death/stroke (8.7% vs 30.7%; P<0.001) and functional impairment (mRS score ≥2 25.4% vs 46.2%; P<0.01).

CONCLUSION

Our results suggest that intervention for unruptured brain AVMs at comprehensive stroke centers across the United States is safe.

Cerebral arteriovenous malformation rupture in pregnancy

A 30-year-old nulliparous woman at 38 5/7 weeks of gestation developed a sudden, severe headache at work and subsequent loss of consciousness. She underwent evaluation in the emergency department. CT and CT angiogram head revealed a large intraparenchymal haematoma with intraventricular extension secondary to ruptured cerebral arteriovenous malformation (cAVM). She was intubated and transferred to a tertiary care centre. The patient underwent caesarean section followed by partial embolisation of the cAVM with planned second embolisation and resection 1 week later. Due to drowsiness and headache, the planned repeat embolisation and cAVM resection were performed 3 days earlier. The patient had a full recovery. Emergency medicine physicians and obstetrician-gynaecologists should be familiar with differential diagnosis of sudden headache in pregnancy and signs of a ruptured cAVM to facilitate early diagnosis, multidisciplinary team approach and timely treatment. Early diagnosis and management of ruptured cAVM are important due to associated morbidity and mortality.

Distribution and characterization of tumor-associated macrophages/microglia in rat C6 glioma

Immunity responses and immunotherapy are novel areas of research for the pathological development and treatment of glioma, the most common brain cancer. Characterization of the subpopulations of infiltrated immune cells may aid in our understanding of the tumor immune response and contribute to the identification of cellular targets for selective immunotherapy. Using a rat C6 glioma model, the present study observed a significant heterogeneity of active macrophages and microglia, including cluster of differentiation 8 (CD8)⁺, endothelial monocyte-activating polypeptide II (EMAPII)⁺ and ED1⁺ cells, mostly in the areas of compact tumor growth and inside or around the pannecrosis. Moreover, the CD8⁺ cells were similar to reactive ED1⁺ and EMAPII⁺ microglia/macrophages in morphology and distribution, but different from the W3/13⁺ T cells. These observations suggest that different subtypes of macrophages and microglia are involved in glioma development and thus, may be potential targets for immunotherapeutic antitumor strategies.

Immunotherapy for malignant glioma using human recombinant interleukin-2 and activated autologous lymphocytes. A review of pre-clinical and clinical investigations

Over the past few years, we and a number of other groups have conducted laboratory experiments and clinical trials of human recombinant interleukin-2 (rIL-2) alone or in combination with autologous 'activated' lymphocytes expressing in vitro tumoricidal activity in order to define toxicity and indicate its potential efficacy in patients with high-grade glioma. Because high rIL-2 concentrations can be attained with considerably less toxicity than with a systemic approach, all of the clinical trials, to date, have chosen a direct route; injecting lymphokine and cells into tumor tissue, the cystic cavity remaining after tumor excision, and/or neural parenchyma surrounding the site of tumor excision. While the rIL-2 therapies, as they have been applied in animal glioma models and patients, are safe, cerebral edema around the site of treatment has been a consistent finding. We have also seen, however, that steroid medications used by patients to control their cerebral edema may depress the anti-tumor activity of rIL-2 by depressing the capacity of lymphocytes to develop normal LAK activity. Although none of the immunotherapies involving rIL-2 have produced cures, the fact that sustained clinical responses have been reported, suggests that such therapies may slow a recurrence of tumor at the site of treatment. Efforts to improve outcome from rIL-2--based immunotherapies for malignant glioma are continuing with manipulation of rIL-2 dosing and scheduling and also with combinations of rIL-2 and other recombinant cytokines.